package com.wcards.controller;

import com.wcards.config.R;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

/*/
文件的上传与下载
 */

/**
 * @author 大黑
 */
@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${wcadrs.path}")
    private String basePath;
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){
        //获取原始文件名字：
        String originalFilename=file.getOriginalFilename();
        String suffix= originalFilename != null ? originalFilename.substring(originalFilename.lastIndexOf(".")) : null;
        String fileName= UUID.randomUUID().toString()+suffix;
        //创建一个目录
        File dir=new File(basePath);
        //判断目录是否存在
        if(!dir.exists()){
            dir.mkdirs();
        }
        try {
            //将文件存储到指定的目录
            file.transferTo(new File(basePath+fileName));
        } catch (IOException e) {
            e.printStackTrace();
        }
        System.out.println(fileName);
        return R.success(fileName);
    }
    /*
     * 文件下载
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //输入流，通过输入流来获取图片
            FileInputStream fileInputStream=new FileInputStream(new File(basePath+name));
            //输出流，通过输出流将文件写回浏览器，在浏览器展示图片
            ServletOutputStream outputStream=response.getOutputStream();
            response.setContentType("image/jpeg");
            int len=0;
            byte[] bytes=new byte[1024];
            while((len=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
